The US obesity epidemic has worsened across the board to include 40 percent of women, 35 percent of men and 17 percent of children and teens, studies released Tuesday found. Efforts to encourage Americans to lose weight have achieved precious little, the research by the Centers for Disease Control and Prevention found. Published in the Journal of the American Medical Association, one study examined data for 2,638 adult men and 2,817 women with average ages of 47 and 48, respectively.